Aspergillus Niger Improves the Nutritional Composition of Apple Pomace by Solid-State Fermentation

Abstract

The effect of solid-state fermentation using Aspergillus niger on the nutritional composition of apple pomace was investigated in this study. Apple pomace was milled to 2 mm and sterilized at 121 °C for 15 min before fermentation. Aspergillus niger strain (ATCC 200345) was cultured and inoculated to apple pomace 104 spores/ml. Raw and fermented apple pomace were analyzed for determination of the crude protein (CP), ash, ether extract (EE), crude fiber (CF), neutral-detergent fiber (NDF), acid-detergent fiber (ADF), and acid-detergent lignin (ADL) content. The CP (P<0.001) and ash (P<0.05) contents of apple pomace were increased after solid-state fermentation. However, A. niger decreased (P<0.001) the CF, NDF, ADF, hemicellulose, NFE and EE (P<0.05) contents of apple pomace. The ADL content of apple pomace was not affected by solid-state fermentation. The results demonstrated that solid- state fermentation using A. niger can improve the nutritional composition of apple pomace.